BLACKSBURG, Va., mar. 14, 2003 - A consortium of researchers lead by VBI Professor, Brett Tyler, recently completed the establishment of a database of gene sequences from the soybean pathogen, Phytophthora sojae. The gene sequences were obtained by sequencing copies of messenger RNA molecules, creating so-called Expressed Sequence Tags (ESTs). Nearly 30,000 sequences were obtained representing over 7000 genes, about half of the pathogen's entire gene set. Nearly 9000 of the ESTs were obtained from P. sojae as it was in the process of infecting soybean tissue, providing an unparalleled insight into the genes the pathogen uses to attack soybean.
The database also includes a smaller number of EST sequences from the potato late blight pathogen Phytophthora infestans, and in future may include EST sequences from additional Phytophthora species.
P. sojae is a member of an obscure kingdom of life known as the Stramenopiles. Stramenopiles are even more distantly related to humans than are green plants and fungi. Many Stramenopiles are destructive plant pathogens, including Phytophthora infestans, which caused the Irish potato famine and the new pathogen that is attacking California oaks (Phytophthora ramorum). Other Stramenopiles include brown seaweeds such as kelp, and unicellular algae that carry out much of the photosynthesis in the oceans, called diatoms.
The ESTs, together with a complete DNA sequence of the P. sojae genome that is currently being completed in collaboration with the DOE Joint Institute in Calfornia, will greatly advance understanding of the biology of the pathogen, and should help identify new ways of controlling the pathogen.
Members of the Phytophtora Genome Consortium include Brett Tyler (Virginia Tech), Mark Gijzen (Agriculture Canada, London), Howard Judelson (University of California, Riverside), Ralph Dean (North Carolina State University) and Mark Waugh (National Center for Genome resources, Santa Fe). Some of the P. infestans EST sequences were contributed by Sophien Kamoun (Ohio State Unviersity), Francine Govers (Wageningen University, The Netherlands) and Donald Nuss (University of Maryland). The Phytophthora Genome Consortium was funded by a $1.0m grant from the USDA Initiative for Future Agriculture and Farming Systems (IFAFS).
March 13, 2003